Vishvarupa Trishiras
The three-headed, six-eyed son of Tvashtri. In the Rigveda he keeps cattle and is killed by Trita and Indra. In the Taittiriya Samhita and Shatapatha Brahmana he is the gods' house priest and the Asuras' sister's son, with one mouth for Soma, one for strong drink and one for food; Indra cuts off his heads, which become three birds. The Mahabharata makes him a blameless ascetic created by Tvashtri to rival Indra.
Sources: Hymns of the Rigveda, tr. R. T. H. Griffith (1896), hymns read for the Vedic layer; The Veda of the Black Yajus School (Taittiriya Sanhita), tr. A. B. Keith (1914); The Satapatha-Brahmana, tr. Julius Eggeling (Sacred Books of the East 12, 41); The Mahabharata, tr. K. M. Ganguli (1883-96), sections read for the Vedic layer · see Vishvarupa Trishiras's web